Volatile organochlorine behavior and remendiation in subsurface environment

地下环境中挥发性有机氯行为及修复

基本信息

批准号：
04650472
负责人：
HIRATA Tatemasa
金额：
$ 1.28万
依托单位：
National Institute for Environmental Studies
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1992
资助国家：
日本
起止时间：
1992 至 1993
项目状态：
已结题

项目摘要

The remediation operation for subsurface environment is so costly, therefore, the success of the remediation totally depends on picking up the suitable techniques to repair the subsurface pollution, corresponding to contaminant existing form in subsurface environment. In this context, soil-gas survey as an option of remote geochemical exploration to identify the pollutant source to determine the sites for making boreholes was developed.The remediation technologies employed in the pollution sites in Japan so far are the soil venting, groundwater extraction and soil excavation to physically remove the contaminants. All of them were applied to the study sites to evaluate the effectiveness and the application limit to the pollution scale. The result shows that the soil venting is so unique and useful to remove the volatile organochlorine from vadose zone. In the study sites, the groundwater extraction was also utilized. The comparison of both removal rates for trichloroethylene revealed th … More at the removal rate by soil venting is one order as high as the groundwater extraction, and both removal rates are going down with operation time. The removal rates by soil venting is reducing more quickly than groundwater extraction, therefore, both removal rates are going to meet each other. After the crossing time, groundwater extraction will overcome the soil venting. In another pollution site, the polluted soil of up to 1,000m^3 under the building was excavated. After the operation, the groundwater extraction has continued to repair th aquifer and leads to uptake about twenty tons of trichloroethylene, reducing the groundwater concentration to near the drinkable limit. The organochlorines are basically little soluble in water so that the groundwater extraction needs fairly long time to repair the polluted aquifer. However, the groundwater extraction holds a possibility to remove much more contaminants, compared to the soil venting and soil excavation. The results obtained in this research mention that the groundwater extraction is inevitable technology for cleaning up the polluted aquifer. Less

因此，地下环境的补救操作是如此昂贵，因此，补救的成功完全取决于拾取合适的技术来修复地下污染，这对应于地下环境中的污染物现有形式。在这种情况下，土壤气体调查是远程地球化学探索的一种选择，以确定污染物来源以确定制造钻孔的地点。到目前为止，在日本污染地点工作的补救技术是土壤排气，地下水萃取和土壤开挖以物理去除污染物的。所有这些都应用于研究地点，以评估污染量表的有效性和应用限制。结果表明，土壤排气是非常独特且有用的，可用于从vadose区清除挥发性有机氯。在研究地点，还利用了地下水提取。三氯乙烯的两种去除率的比较表明，以土壤排气的去除速率有更多的秩序与地下水提取一样高，并且两种去除率随着操作时间而下降。与地下水的提取相比，土壤排气的去除率更快地降低了，因此，这两个去除率都将相遇。穿越时间后，地下水提取将克服土壤排气。在另一个污染地点，挖掘了建筑物下面最高1,000m^3的污染土壤。手术后，地下水的提取继续修复TH含水层，并导致大约20吨三氯乙烯的吸收，从而将地下水浓度降低到可饮用的极限接近。有机氯基本上几乎没有固体，因此地下水提取需要很长时间才能修复污染的含水层。但是，与土壤通风和土壤发掘相比，地下水提取有可能去除更多污染物。在这项研究中获得的结果提到，地下水提取是不可避免的技术来清理污染的含水层。较少的